Levy, Wilbert J., author
Amsco School, 1982
Buku Teks
Ross, Janet, author
Harper & Row , 1965
Buku Teks
Taylor, Grant
Saxon Press, 1956
Buku Teks
Ingram, Beverly
Cambridge University Press , 1988
Buku Teks
Robinson, Lois
Harper & Row , 1967
Buku Teks